1/1 mtg card MTG's Lord of the Rings cards include an ultra-rare one-of-one One Ring Rules Text: creature, enters, battlefield,

You can't change your mind and choose not to sacrifice anything

5 - Wan Shi Tong, Librarian - $54 Wan Shi Tong, Librarian can rack up counters, has Flash, Flying, and Vigilance, and gives you card draw, too

Mind Bomb is another card that sees play occasionally, for its use in discarding unwanted creatures from hand, but I think its just worse than all of the cards above

Being able to prevent damage to your creatures is good, and its even better when your commander has mana sinks built into them

With the advent of Saga creatures, it's much easier to get into a situation where a Saga on the battlefield loses all of its abilities but is still a Saga enchantment